The TSA can conduct a full-body search, prison-style, on everyone who gets near an airport: we can lock down the country, and treat everyone like a potential criminal, conducting random searches on the streets like they’re already doing in New York City. We can turn the country into one big prison yard, and still the terrorists will get through, eventually.
They’ll get through because we’re creating new enemies every day, many thousands of them, as we extend our perpetual "war on terrorism" to new regions, and claim more blood sacrifices on the altar of our new god, Revenge. The conduct of our foreign policy for the past decade or so ensures that the supply of terrorists will be endless, as the relatives and loved ones of our victims come gunning for us. By hook or by crook they will get us – unless the cycle of revenge is stopped.
What can stop it is a revolt against the TSA that becomes a widespread rebellion against our crazy, enemy-creating foreign policy. Short of that, the anti-TSA movement could easily backfire: the great danger is that the government will adopt, as an "alternative" to the physically intrusive methods of the TSA, methods that go much farther in destroying what little is left of our liberties.